Warm air is frequently hurnid, i.e. it contains entrained water vapor. During operation of an air conditioning system in a cooling mode, the evaporator reduces the temperature of the air passing though it to a temperature below the dew point. In that condition, water vapor condenses on the evaporator. Means are provided to collect the condensed water and to direct it to the outdoor section of the air conditioner where at least a portion thereof is quite often directed upon the system's condenser heat exchanger to improve the operating efficiency of the system. Excess condensate, and rain water that may pass into the outdoor unit through openings in the housing of the air conditioning unit, collect in the basepan and it is common practice to provide a drain outlet for conducting such excess to an appropriate disposal location. In small room air conditioners, quite often the basepan of the unit is made from a molded plastic material and a condensate drain may be readily molded into the plastic basepan.
In units having metal basepans the rear of the basepan may be configured to provide an open channel for disposal of condensate. Such arrangements, however, do not facilitate the attachment of a drain hose or the like to collect and direct the condensate to a desired location rather, they just allow dripping of the condensate through the channel from which it falls, under the influence of gravity, to the ground or whatever happens to lie under the unit.
In larger air conditioners having metal basepans, an optional drain opening is sometimes provided in the bottom of the basepan. A separate component is provided which may be assembled to the basepan upon punching out the opening, which will allow drainage of the condensate therethrough and which will provide a fitting on the lower side of the basepan for installation of a drain hose or the like. Such components are usually shipped separately and must be installed by the end user during installation or following installation in order to avoid damage to the drain fitting extending below the basepan. It being understood that, during installation, the lower part of the basepan quite often is slid horizontally across the support surface for the air conditioner, whether it be a window or a rectangular opening in a wall of the room to be cooled.
It is accordingly desirable to have a simple condensate drain arrangement for an air conditioner having a metal basepan, which will facilitate drainage of the excess condensate from the rear thereof and facilitate attachment of a disposal hose thereto for direction of the condensate to a desired collection location.